1. Add dateformat "Locale" with ICU; uses current locale for date
parsing. ICU's locale date parser may parse "3 May 2023" or
"2024年9月13日" (LC_TIME=zh_TW.utf8) and maybe others.
2. Augment d-m-y m-d-y and y-m-d with boost UK/US/ISO parsers. This allows
CSV import of dates with months as words as "30 Sep 2023" or
"May 4, 1978" or "2023-Dec-25". Note boost parser cannot recognise
2-digit years, therefore "30 Sep 24" is invalid.
Extract functions LDT_from_date_time and LDT_from_date_daypart
to avoid duplicate code. Handle date-times in start-of-DST transitions
and better handle those in end-of-DST transitions. Test the results.
Turns out the stream facet parser is really slow. Since we have a
well-constrained universe of input formats we don't really need that
overhead. This got a 33% improvement in loading a large SQLite database.
It is split into
- /libgnucash (for the non-gui bits)
- /gnucash (for the gui)
- /common (misc source files used by both)
- /bindings (currently only holds python bindings)
This is the first step in restructuring the code. It will need much
more fine tuning later on.
